Humidifier



FIG. 1 is a front perspective view of a humidifier according to the invention;

FIG. 2 is a left side perspective view thereof;

FIG. 3 is a right side perspective view thereof;

FIG. 4 is a rear perspective view thereof;

FIG. 5 is a top perspective view thereof; and,

FIG. 6 is a front left perspective view thereof.

The broken line showing of environmental structure in FIGS. 1-6 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a humidifier, as shown and described. 